Eley and other "match grade" bullets are a consistent .224.. A match grade barrel, such as Lilja, has a bore of .217 and a groove diameter of .2215Some barrel makers offer a "tight" barrel of .220 groove/.215 bore. I am not a fan of "Tight is Right"..A majority of the 41 barrels are .214 or less.. One reason, they often don't shoot well. For BE shooting, stay with the standard velocity.